nsScriptEventManager.cpp

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- *//* ***** BEGIN LICENSE BLOCK ***** * Version: MPL 1.1/GPL 2.0/LGPL 2.1 * * The contents of this file are subject to the Mozilla Public License Version * 1.1 (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/ * * Software distributed under the License is distributed on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License * for the specific language governing rights and limitations under the * License. * * The Original Code is Mozilla Communicator * * The Initial Developer of the Original Code is * Netscape Communications * Portions created by the Initial Developer are Copyright (C) 2002 * the Initial Developer. All Rights Reserved. * * Contributor(s): * Rick Potts <rpotts@netscape.com> * * Alternatively, the contents of this file may be used under the terms of * either the GNU General Public License Version 2 or later (the "GPL"), or * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), * in which case the provisions of the GPL or the LGPL are applicable instead * of those above. If you wish to allow use of your version of this file only * under the terms of either the GPL or the LGPL, and not to allow others to * use your version of this file under the terms of the MPL, indicate your * decision by deleting the provisions above and replace them with the notice * and other provisions required by the GPL or the LGPL. If you do not delete * the provisions above, a recipient may use your version of this file under * the terms of any one of the MPL, the GPL or the LGPL. * * ***** END LICENSE BLOCK ***** *//* * Class that allows finding an event handler <script> node (one using * FOR="....") for a given event and dispatching the event to that * node. */#include "nsScriptEventManager.h"#include "nsString.h"#include "nsReadableUtils.h"#include "nsIDOMNode.h"#include "nsIDOMHTMLScriptElement.h"#include "nsIDOMHTMLObjectElement.h"#include "nsIDOMDocument.h"#include "nsIScriptElement.h"#include "nsIScriptEventHandler.h"#include "nsIDocument.h"
nsScriptEventManager::nsScriptEventManager(nsIDOMDocument *aDocument)
{
nsresult rv;
rv = aDocument->GetElementsByTagName(NS_LITERAL_STRING("script"),
getter_AddRefs(mScriptElements));
}
nsScriptEventManager::~nsScriptEventManager()
{
}
NS_IMPL_ISUPPORTS1(nsScriptEventManager, nsIScriptEventManager)
NS_IMETHODIMP
nsScriptEventManager::FindEventHandler(const nsAString &aObjectName,
const nsAString &aEventName,
PRUint32 aArgCount,
nsISupports **aScriptHandler)
{
nsresult rv;
if (!mScriptElements) {
return NS_ERROR_FAILURE;
}
// Null out the return value...if (!aScriptHandler) {
return NS_ERROR_NULL_POINTER;
}
*aScriptHandler = nsnull;
// Get the number of script elements in the current document...
PRUint32 count = 0;
rv = mScriptElements->GetLength(&count);
if (NS_FAILED(rv)) {
return rv;
}
//// Iterate over all of the SCRIPT elements looking for a handler.//// Walk the list backwards in order to pick up the most recently// defined script handler (if more than one is present)...//
nsCOMPtr<nsIDOMNode> node;
nsCOMPtr<nsIScriptEventHandler> handler;
while (count--) {
rv = mScriptElements->Item(count, getter_AddRefs(node));
if (NS_FAILED(rv)) break;
// Check if the SCRIPT element is an event handler.
handler = do_QueryInterface(node, &rv);
if (NS_FAILED(rv)) continue;
PRBool bFound = PR_FALSE;
rv = handler->IsSameEvent(aObjectName, aEventName, aArgCount, &bFound);
if (NS_SUCCEEDED(rv) && bFound) {
*aScriptHandler = handler;
NS_ADDREF(*aScriptHandler);
return NS_OK;
}
}
// Errors just fall of the end and return 'rv'return rv;
}
NS_IMETHODIMP
nsScriptEventManager::InvokeEventHandler(nsISupports *aHandler,
nsISupports *aTargetObject,
void * aArgs,
PRUint32 aArgCount)
{
nsCOMPtr<nsIScriptEventHandler> handler(do_QueryInterface(aHandler));
if (!handler) {
return NS_ERROR_FAILURE;
}
return handler->Invoke(aTargetObject, aArgs, aArgCount);
}